Introduction: Injury to deep neck structures should be considered during emergency room (ER) admissions in patients with a chief complaint of swelling in the neck, particularly when there is a history of trauma to the neck. Life-threatening conditions should be assessed, diagnosis should be made using appropriate imaging modalities, and treatment should be planned accordingly. Case Report: A 30-year-old male presented to the ER with the chief complaint of a swollen neck 2 h after he fell off a bicycle. Based on the ultrasound and computed tomography analysis, he was diagnosed with isolated submandibular injury. Conclusion: Isolated submandibular injury following a blunt trauma is a rare condition. Obtaining appropriate imaging modalities is helpful in confirming the diagnosis. Patients with blunt trauma should also be carefully assessed for other, nonapparent injuries.
